In a large skillet, cook bacon and onion over medium heat until bacon is crisp and onion is tender. Drain & clean out pan.
Meanwhile, place beans in a large saucepan and cover with water. Bring to a boil. Cook, uncovered, for 7 minutes or until crisp-tender; drain well. Add to bacon oil to the pan and saute the green beans. Sprinkle with salt and pepper; toss to coat. Top with bacon bits and serve immediately.